Only about one-third of eastern Lake Erie is frozen over. The average temperature here has been 5 to 6 degrees warmer than normal throughout December and January. And the snow total, so far this winter, lags almost 30 inches behind historic snowfall averages through Feb. 25.

Once again, the region has had a milder winter than normal, although nothing compared with last year’s.

That’s back-to-back soft winters, following last year’s thaw-fest.

But there’s one message from the experts: Two years don’t make a trend.

“We can have back-to-back winters that are on the far end of the spectrum – whether it’s a lot of snow or a lack of snow – but you shouldn’t use two years as a trend,” National Weather Service meteorologist David Thomas said.

Last winter was the really mild one, marked by only 36.7 inches of snow for the whole season, average daily temperatures hovering 5 degrees above normal all winter and a Lake Erie that never froze.

Toss in the ill-fated attempts to play a pond-hockey tournament on Erie Basin Marina ice the last two Februarys, and it’s enough to get people chatting about “global warming.”

Historically, there’s plenty of evidence about two-year “trends.”

Only old-timers can remember the winters of 1947-48 and 1948-49, when the snowfall totals were less than half the long-term average, at 42.1 and 40.1 inches, respectively.

“Those were two winters that had well-below-normal snowfalls,” Thomas said. “Now we’re back to that.”

Another great example on the other end of the weather spectrum: the winters of 1976-77 and 1977-78, the first and third whitest winters ever, with snowfall figures of 199.4 and 154.3 inches. Yikes. Luckily, Buffalo didn’t quite turn into an annual Siberia after that.

“After two years, you can’t really get a good trend,” Thomas said. “We always have ups and downs in the weather. You have to look at a longer time period to get a feel for the trend.”

The National Weather Service, with its emphasis on forecasts and statistical summaries, tries to steer away from the whole global-warming debate.

Others don’t.

Ryan McPherson, chief sustainability officer at the University at Buffalo, pointed out that weather and climate are not the same thing. But weather can provide a meaningful glimpse into climate patterns.

“Whether it is these extreme weather events, like Irene and Sandy, or the swings in our weather the last few years, those certainly support the megatrend of a warming planet, which we can clearly show,” McPherson said. “Climate change is happening.”

The facts also show that Lake Erie has been slow to freeze this winter, especially at its eastern end.

“It’s really thin,” said Paul Yu, an engineer with the U.S. Army Corps of Engineers in Buffalo. “One hot, sunny day would melt it all.”

Engineers from the Corps had been scheduled to land a plane on lake ice Feb. 14 to measure its depth. Satellite images taken a couple of days earlier showed ice there, but when the day arrived it was gone, leading the Corps to cancel the plane ride.

“We have another one scheduled for March 12, provided there’s ice there,” Yu said. “Right now, it doesn’t look good.”

While we clearly have enjoyed a relatively mild winter, it’s not exactly the Fourth of July out there, either. After all, we’re still talking winter-storm watches and advisories, and the ice still chokes Lake Erie along the Buffalo Harbor.

Monday, the U.S. Coast Guard was forced to scrap its plans for an ice-breaking operation to make way for a commercial carrier headed to the Buffalo outer harbor.

The culprit – jagged ice formations known as “brash ice” that were 5 to 8 feet thick, according to Lt. Adrian Palomeque, the Detroit-based ice officer for the U.S. Coast Guard

“Normally, it’s not too much of an issue,” he explained. “Our vessels are designed to withstand that. But conditions were such that it was taking a long time to make any progress.”

The carrier, the Algoma Enterprise, is making its way to Port Colborne, Ont., instead.

Nearly every winter, the Coast Guard conducts two ice-breaking operations in the Great Lakes. Last year, the operation that covers Lake Erie was never started because of the mild winter, Palomeque said.

This year, both operations have been back up and running, he said.

Other facts, though, point to a relatively mild winter:

• The region remains snow-deprived, with only 47.6 inches of snow through Monday at the National Weather Service office in Cheektowaga. That’s almost 30 inches short of the 30-year average of 77.1 inches through the same date. The 30-year average for the whole winter is 94.7 inches.

• It hasn’t been a sun-splashed picnic every day, but this winter’s temperatures, on the whole, remain significantly warmer than normal.

In rough terms, November and February (so far) have been about 1 degree colder than average. But December, with an average mean temperature of 36.3, and January, with an average of 30.0, have been 5 to 6 degrees milder than normal.

And forecasters expect winter to go out with fairly mild temperatures.

• The National Weather Service keeps track of the ice-covered date for Lake Erie, when the bulk of Buffalo Harbor is covered with ice.

This year’s date was Feb. 2.

“If you look at the last 30 years, the average is Jan. 21,” Thomas said. “This year, the date was almost two weeks later.